ROCK ISLAND - It isn't a simple jaunt in a car to see the Pottawatomie Lighthouse at the northern tip of Rock Island. It's an adventure which rewards planning and time with spectacular scenery and the dominant sound of Lake Michigan waves lapping the rocky coast.

While Rock Island is the home of Wisconsin's oldest lighthouse, it's also home to Door County's oldest known standing structure, the lighthouse privy.

The first Pottawatomie Lighthouse and its two-seat outhouse were built in 1836. Both structures were constructed with local stones and mortar years before Wisconsin became a state, said Tim Sweet, a member of the Friends of Rock Island, also known as FORI.

Around the 1850s, the lighthouse mortar was crumbling and a new building was constructed in 1858.

But not the outhouse.

The small structure was built to last, Sweet said.

It remained the privy for decades of lightkeepers, their families and visitors until the lighthouse site was abandoned in 1946 following automation of the powerful light. For almost 200 years, a light has glowed from Rock Island marking the passage for ships traveling from Michigan to Green Bay.

A trip to Rock Island is an immersion into solitude and nature, said Sweet.

It's also an opportunity to touch history.

"When people find that out, they are sort of surprised," said Colleen Andrews of Almond, who every summer volunteers with her husband to stay at the restored lighthouse for a week and provide tours of the structure for visitors.

Tours are available through Oct. 8, which is also the last day of ferry service to Rock Island.

"While you can't use the outhouse now, people are interested to know that it predates the lighthouse," Andrews said.

The designation of the Rock Island lighthouse privy as Door County's oldest standing structure is not a proven fact, said Trudy Herbst, director of the Door County Historical Society.Rather it's a designation given the outhouse since there's nothing recorded about an older building still standing, Herbst said.

The earliest settlements of European immigrants were on "Rock Island and Chambers Island, so it's possible that outhouse is the oldest building still standing," Herbst said.

Seeing the oldest Door County structure isn't the draw for visitors to Rock Island.

"This place is a gem — it's a beautiful island to hike around, there's a lot of history and, of course, there's this lighthouse which I think is the finest in all of Wisconsin," said Kirby Foss of Washington Island, who admits he "might be a bit biased." He served as the Rock Island Park Ranger from 1976-1991 and, later, as the park superintendent from 2000 to 2011.

Rock Island, including the historic lighthouse, are part of the state's park system and are managed by the Department of Natural Resources, which partners with FORI. This partnership resulted in the restoration of the 1858 lighthouse and privy.

The highlight for many island visitors is their hike to Pottawatomie Lighthouse and the tour of the structure, Foss said, noting the information about the privy is more of an oddity that amuses visitors.

The miles of hiking trails aren't difficult and provide visitors with vistas of a former fishing village, old cemeteries and one of the finest sand beaches in the state, Foss said.

"And of course there's the magnificent boat house, which is a treasure, too," he said.

In 1914, Chester H. Thordarson bought most of the island's 900 acres and built a variety of structures, including an iconic boathouse with a great hall above it, in a style reminiscent of his homeland — Iceland. The DNR purchased the estate from Thordarson's heirs in 1965.

"Rock Island is a magical place, and there is nothing like it anywhere else," Andrews said. She and her husband had camped on the island for 40 years and, she said, "jumped" at the opportunity to participate in the lighthouse renovation and serve as docents.

"It's very special to live in a lighthouse, and the neat part of it is sharing it with people who have never seen a lighthouse before," Andrews said.

Tours generally are about 20 minutes but can be longer if there aren't waiting visitors.

"Oh my, there is so much history to share; our tours sometimes depend on the interest of visitors," Andrews said.

The lighthouse bedroom used by the docents, during their week providing tours, has large windows opening to Lake Michigan.

"I call it the best bedroom in Wisconsin because you can see all the way to Michigan," she said.

Visitors to Rock Island travel from all over the state, nation and world.

"We ask visitors to sign a guest book, and it's remarkable how people make it a point to travel to Rock Island," Andrews said.

"I especially enjoy it when we have visitors who are related to someone who was a lightkeeper. Over the years I've met the grandchildren, nieces and nephews of many lightkeepers," she said.

The land under the privy was the site of an archaeological dig but nothing of note or historical interest was found, said both Andrews and Sweet.

Other archaeological digs have focused on the Native Americans who inhabited the island. The lighthouse is named for the Potawatomi who originally called the island home.

"There's a lot to see at this park, and it's hard for me to pick a favorite," said Foss, the retired Rock Island park superintendent. "It's a beautiful island to hike around and there's a lot of history. It's a gem among Wisconsin's parks."

To visit Rock Island

Things to know:

First, motorized vehicles and bicycles aren't permitted on this state park.

Second, it's almost a two-mile hike, mainly uphill, to reach the historic lighthouse